Rotary-cutter attachment for portable chain-saw motor



Aug. 11', 1959 E. G. AUSTIN ROTARY-CUTTER ATTACHMENT FOR PORTABLE CHAIN-SAW MOTOR Filed Aug. 15, 1957 INVENTOR. G. H u sh n Eldo BY United States Patent f ROTARY-CUTTER ATTACHlVIENT FOR PORTABLE CHAIN-SAW MOTOR Eldon G. Austin, Molalla, Oreg.

Application August 13, 1957, Serial No. 677,893

5 Claims. (Cl. 144-208) This invention relates to apparatus for routing timbers and more particularly to a novel attachment for a portable motor means which includes a rotatable cutter or routing member adapted to be driven by the motor thereby to cut away material engaged by the router.

Generally, it is an object of this invention to provide a novel, portable attachment apparatus to be used with a portable motor means which is characterized by a relatively simple construction yet which is highly efficient in operation, safe to use, and readily adjustable so as to accommodate variations in motors used therewith, and to produce variable cutting characteristics. The invention has particular utility as a bark-rossing device when used in conjunction with a portable chain-saw motor of a type which is commercially available and in wide use.

Log-barking machines of various types are well known. However, most of these machines are really only suitable for removing the bark from relatively large-diameter logs of the type employed in sawmills and plywood manufacturing plants. The device according to the invention is particularly well suited for economical, oneman debarking of smaller-diameter logs of the type used for poles, etc., although the device can be used on any size log.

While rossing the bark from a log is recognized as being necessary prior to carrying out manufacturing operations on the log, it is not being uniformly practiced because of the expense involved in procuring suitable equipment. This invention contemplates an attachment wherein the portable motor of a conventional, portable chain saw may be easily and readily converted with a minimum amount of time into a highly efiicient bark rosser. While the invention has particular utility in the rossing of logs, it will be obvious that the invention can also be used for other routing operations.

The portable apparatus includes a shield which forms the support or base to which a portable motor is attached. The shield is so conformed that it prevents chips and wood particles from being thrown by the routing member against the face of the operator of the machine. Front and rear support means are included for supporting the shield over the log being processed. The rear support is resilient, enabling control of the depth of cut of the rotatable routing member by pressing down against the bias of the spring. The routing member is rotatably mounted in a novel mounting structure which accommodates longitudinal and vertical adjustment of the routing member whereby (1) proper tension can be created in the power-transmitting means driving the routing member, and (2) a means is provided for varying the amount of downward pressure needed to obtain a given depth of cut.

A further feature of this invention is the inclusion of a novel attaching means for detachably connecting the portable motor of a chain saw to the shield member of the apparatus. The attaching means includes a planar surface which is adapted to be aligned with the planar surface found in most chain saws and used for supporting A 2,898,959 Patented Aug. 11, 1959 the blade portion of a chain saw. Upon alignment of the two planar surfaces, the driving member of the chainsaw motor and the driven member which rotates the rotatable routing member move into alignment. In this way, excessive wear of the power-transmitting means employed for driving the routing member is prevented.

The rotatable routing member of the attachment is carried by the shield or base member substantially forwardly of the driving member for the portable chain-saw motor when the saw motor is secured in position on the shield member. trolling the depth of cut made by the routing member by reason of the fact that the reaction force produced by the routing member in cutting into a layer of wood tends to be transmitted downwardly on the rear support for the apparatus so that the rear support assists in steadying the apparatus.

In a preferred embodiment of this invention, the rear support for the shield member of the apparatus takes the form of a resilient skid member depending downwardly from the shield member from approximately the longitudinal center of the shield member. The rear end of the device may be moved laterally to either side to control direction of the apparatus by skidding this member over the surface of a log or timber. The forward support for the apparatus preferably includes a pair of star wheels spaced laterally to either side of the longitudinal center of the shield member. The star wheels grip into the timber being processed and prevent the apparatus from skidding off to one side. Further, by providing lateral support for the apparatus to either side of its longitudinal center, the apparatus is prevented from tipping over on its side.

These and other objects and advantages are attained by the present invention, various novel features of which will become more fully apparent as the following description is read in conjunction with the accompanying drawings, wherein:

Fig. l is a side view of the routing apparatus of this invention, illustrating the front and rear supports for the apparatus and the relative location of the rotatable routing member carried thereby and indicating the approximate position of a portable chain-saw motor which is connected to the apparatus;

Fig. 2 is a bottom view of the apparatus illustrated in Fig. 1; and

Fig. 3 is an end view further illustrating the front support mechanism for the apparatus and the demountable control bar included in the apparatus to assist in controlling depth of cut.

Referring now to the drawings wherein an embodiment of this invention is illustrated, the portable routing aparatus is indicated generally at 10. Carried on top of the apparatus is a portable chain-saw motor indicated by the dotted outline 11. The driving member of the motor, illustrated by pulley 13, is connected to an output shaft 14 of the motor 11.

The routing apparatus comprises an elongated shield or base member or plate, indicated at 16, which provides the support for the portable motor carried by the routing apparatus. In the embodiment illustrated, the shield member 16 has a substantially squared-0E forward end 17 and a diminished tongue portion 18 protruding outwardly at the rear end of the shield member and lying substantially along the longitudinal center thereof.

Extending downwardly from the tongue portion 18 of the shield member and affixed to the tongue portion with a lower end portion thereof providing support for the shield member along substantially its longitudinal center is a resilient skid member 21. The skid member 21 constitutes the rear support for the apparatus. The skid member is comprised of spring steel, and is affixed to This provides for greater ease in con' the shield member as by screws 22. The skid member has a gradually curved lower end which enables the rear end of the routing apparatus to move smoothly over a piece of timber being processed. In the construction shown in the drawings, the lower end of the skid member has substantially the same width as the upper end of the member, although other shapes will occur to those skilled in the art;

Carried forwardly of the shield member and depending therefrom is a rotating front-support mechanism indicated at 26. This mechanism includes a mounting bar 27 secured to the shield member as by screws 28. At the forward end of the mounting bar are a pair of star Wheels 29, 31, respectively. The star wheels 29, 31 are rotatably carried on a pin 32 fixed in 'and extending through mounting the bar 27 with its outer ends bent downwardly relative to the mounting bar '27. Star wheels are advantageous, since they give positive tracking and tend not to become clogged with foreign matter.

' The bend of the pin 32 imparts a cant or tilt to the star wheels which gives stability to the apparatus. The angle of inclination of each star wheel normally ranges from between about two to about five degrees from a perpendicular. The star wheels are rotatably mounted on the pin 32 by means of washers 33 and cotter pins 34 which secure the star wheels against bushing members 36.

Depending downwardly from the shield member intermediate the front and rear supports are a pair of mounting portions indicated at 41 and 42. The mounting portions are carried on either side, respectively, of the shield member and provide a means for mounting a rotatable routing member 46. The routing member is carried Within the peripheral confines of the shield member so that material cut out by the routing member tends to be thrown up against and deflected by the shield member.

The rotating member 46 comprises a core portion 47 carried on and secured to a shaft 48 and a pair of knives 49, 51 with their edges extending in opposite directions from the core. A plurality of knives, three or more, may be suitably mounted on the core. These knives may have a linear edge, or the edges may be curved convexly or concavely as desired. The shaft 48 is rotatable in a pair of bearing assemblies 52, 53.

The bearing assemblies 52, 53 are mounted in a pair of eccentric elements 54 and 55, respectively. These eccentrics take the form of circular disks which carry the bearing assemblies so that the center of the shaft 48 is displaced from the radial center of the disks. The disks are secured to the mounting portions by clamping arms 56 integral with the mounting portions. The free ends of these arms are tightened onto the base of the mounting portions as by adjustable screws 57.

Afiixed to one end of the shaft 48 is a pulley 61. The pulley 61 is connected to the driving member of the portable chain-saw motor as by belt 62. Preferably a belt with a fairly positive grip is employed, such as a Gemmer timing belt sold by the US. Rubber Co., or a flat rubber belt, or a chain drive. With a chain drive, lubrication may be done using the existing oiling system of the motor.

By rotating the eccentrics 54, 55, the position of the shaft 48 may be adjusted both vertically and longitudinally of the shield member. This affords a means for adjusting the tension in the belt 62. It also permits adjustment in the amount of pressure exerted on the rear end of the apparatus required to produce a given depth of cut. This is by reason of the fact that longitudinal adjustment of the routing member varies the length of the lever arm between the star wheels (which act as a fulcrum) and the routing member.

The portable motor of the chain saw is secured to the top of the shield by means of brackets such as brackets 66, 67, clamping the chain-saw motor through the bandles for the motor. Chain saws currently available on the market conventionally have a blade portion which is detachably aifixed as by screws or nuts to the housing for the saw motor and which carries the cutting chain for the chain saw. This blade is conventionally mounted on a planar surface included in the housing structure and milled so that a blade mounted on the surface lies in analigned position with respect to the motor drive. This invention contemplates attaching the portable chainplanar surface 72 presented by one of the mounting portions 41. The bracket is afiixed to the motor housing and to the shield member in a suitable manner as by screws 81. By such a construction, a means is provided for aligning the driving member of the chain-saw motor with the driven member or the pulley 61 aflixed to the shaft 48 driving the routing member. This reduces wear between the power-transmitting means or belt interconnecting these two members.

Secured to the front end of the mounting portions 41, 42 as by screws is a guard member 82. The guard member includes a pair of slots 83, 84, at either of its ends, respectively, which accommodate vertical positioning of the guard member relative to the mounting portions. The guard member enables an operator to limit the depth of cut made by the routing member of the apparatus.

It will be noted that the routing member is carried forwardly on the shield member intermediate the driving member or pulley 13 of the chain-saw motor and the front support 26. By such a construction, handling of the apparatus is considerably improved.

Referring to Fig. l, the routing member is driven in a clockwise direction in the figure. When the routing member encounters a relatively tough obstruction, the reaction force set up is exerted downwardly on the rear support 21, and the rear support assists the operator in holding the apparatus at an even depth.

While there has been described only one embodiment of this invention, it is obvious that modifications and variations may be made without departing from the inventive concept thereof. It is desired not to be limited to the particular embodiment illustrated, but to cover all modifications and arrangements which would be apparent to one skilled in the art and that come within the scope of the appended claims.

It is claimed and desired to secure by Letters Patent:

1. Portable apparatus for routing timbers comprising an elongated shield member, a resilient rear support means extending downwardly from the rear end of said shield member with a lower portion thereof supporting said shield member along substantially its longitudinal center, a rotating front support means extending downwardly from the front end of said shield member with lower portions thereof supporting said shield member at points spaced to either side, respectively, of its longitudinal center, a pair of mounting portions depending from said shield member intermediate said front and rear support means, a rotatable routing member carried by said mounting portions, a driven member at one end of said routing member for turning said routing member, and attaching means for detachably connecting a portable chain-sawmotor means to the upper side of said shield member, said portable chain-saw-motor means having a driving member and a planar surface normally supporting a saw-blade portion for said chain-saw-motor means, said attaching means having a planar surface adapted to be aligned with the planar surface of said chain-saw-motor means and operable when the two planar surfaces are aligned to align the driving member of said chain-sawmotor means and the driven member connected to said routing member.

2. Portable apparatus for routing timbers comprising an elongated shield member, a resilient skid member depending downwardly from the rear end of said shield member from approximately the longitudinal center for said shield member, a pair of laterally spaced star wheels rotatably carried at the forward end of said shield member and to either side of its longitudinal center, respectively, means for detachably connecting a portable motor means to the upper side of said shield member, said motor means having a driving member carried to one side thereof, a pair of mounting portions depending from said shield member intermediate said star wheels and resilient skid member, and a rotatable routing member rotatably carried by said mounting portions, said routing member having a driven member connected thereto, said routing member and driven member being carried by said mounting portions forwardly of the driving member of said motor means.

3. Portable apparatus for routing timbers comprising an elongated shield member, a resilient rear support means extending downwardly from the rear end of said shield member with a lower portion thereof supporting said shield member along substantially its longitudinal center, a rotating front support means extending downwardly from the front end of said shield member with lower portions thereof supporting said shield member at points spaced to either side, respectively, of its longitudinal center, attaching means for detachably connecting a portable chain-saw-motor means to the upper side of said shield member, said portable chain-saw-mo-tor means having a driving member and a planar surface normally supporting a saw-blade portion for said chain-saw-motor means, a pair of mounting portions depending from said shield member and spaced longitudinally along said shield member intermediate said front support means and rear support means, and a rotatable routing member adapted to be driven by said chain-saw-rnotor means rotatably carried by said mounting portions, said routing member having a driven member connected thereto, said attaching means having a planar surface adapted to be aligned with the planar surface of said chain-saw-motor means and operable when the two planar surfaces are aligned to align the driving member of said chain-saw-motor means and the driven member connected to said routing member, said routing member and driven member being carried by said mounting portions forwardly of the driving member of said motor means, said mounting portions including means for vertically positioning said routing member relative to said shield member.

4. Portable apparatus for routing timbers comprising an elongated shield member, support means at the forward and rear ends of said shield member for supporting the same, a pair of mounting portions depending from said shield member intermediate said forward and rear ends, a rotatable routing member rotatably carried by said mounting portions, a driven member connected to said routing member, and attaching means for detachably connecting a portable chain-saw-motor means to the upper side of said shield member, said portable chainsaw-motor means having a driving member and a planar surface normally supporting a saw-blade portion for said chain-saw-motor means, said attaching means having a planar surface adapted to be aligned with the planar surface of said chain-saw-motor means and operable when the two planar surfaces are aligned to align the driving member of said chain-saw-motor means and the driven member connected to said routing member.

5. Portable apparatus for routing timbers comprising an elongated shield member having an expansive, substantially continuous lower surface operable to deflect chips thrown thereagainst, attaching means for detachably connecting a portable chain-saw-motor means having a rotatable driving member to the upper side of said shield member with the chain-saw-motor means carried rearwardly of the forward end of said shield member and with said shield member in shielding relation beneath substantially the entire expanse of the lower portions of said chain-saw-motor means, a rotatable routing member and means mounting the same forwardly on and beneath said shield member, a driven member connected to said routing member, said attaching means detachably connecting said chain-saw-motor means to said shield member with said driving member in substantially a common plane with said driven member and with said routing member and driven member being carried by said shield member forwardly of the driving member of said chain-saw-motor means, and support means at the forward and rear ends of said shield member for supporting the same above a timber.

References Cited in the file of this patent UNITED STATES PATENTS 1,701,912 DeWalt Feb. 12, 1929 1,802,800 Wilderson Apr. 28, 1931 2,681,669 Falkman et al June 22, 1954 2,780,252 Gyllenberg Feb. 5, 1957 FOREIGN PATENTS 526,647 Germany June 8, 1931 1,122,198 France May 14, 1956 

